The instant invention relates to 4(hydrocarbylthio)acetoacetic esters defined according to the genus: ##STR2## wherein R.sub.1 represents C.sub.2 -C.sub.6 aliphatic hydrocarbyl and R.sub.2 represents hydrogen or C.sub.1 -C.sub.2 aliphatic hydrocarbyl and uses thereof in augmenting or enhancing the aroma or taste of foodstuffs and chewing gums.
There is a continuing search for food flavor compositions which can vary, fortify, modify, enhance, augment or otherwise improve the flavor and/or aroma of foodstuffs and chewing gums. To be safisfactory, such compositions should be stable, non-toxic and blendable with other ingredients to provide their own unique flavor and aroma nuances without detracting from the co-ingredients of the formulations in which they are used. Preferably, such compositions should be naturally occurring or present in natural foodstuffs so that their ingestible safety can be readily recognized. These materials should be capable of being synthesized in a simple and economical manner. Thus, the need for safe flavors in the mushroom, gooseberry, broccoli, pineapple, onion, cashew juice, tropical fruit, apricot, kiwi, sour cream, dairy, salt substitute, strawberry, plum, tomato, green pepper, garlic and potato flavor area is well known, particularly in the ice cream, yogurt flavor and flavored gelatin dessert areas. More specifically, there is a need for the development of non-toxic materials, which can be used to replace natural materials not readily available having gooseberry, mushroom, broccoli, pineapple, fresh oniony, cashew juice-like, fruity, green, apple, kiwi-like, earthy, radish, fresh green, juicy, ripe tomato-like, potato skin-like, green pepper, garlic and ripe plum-like aroma and taste nuances.
Hydrocarbyl substituted thioesters are known in the field of augmenting or enhancing the aroma and/or taste of foodstuffs and chewing gums. Thus, U.S. Pat. No. 3,904,556 issued on Sept. 9, 1975 (Class 252, subclass 522), a division of Ser. No. 301,524 (U.S. Pat. No. 3,870,800) discloses methylthio butanoic acid esters useful in augmenting or enhancing sweet, roasted, nut-like, dairy, vegetable, fruity, cheesey, and onion-like aromas and tastes. U.S. Pat. No. Re. 30,370 discloses thioesters such as methyl-3-(ethylthio)thiopropionate, ethyl-3-(methylthio)thiopropionate, methyl-3-(methylthio)thiopropionate and ethyl 3 (ethylthio)ethylthiopropionate in augmenting or enhancing various aroma and taste profiles, e.g., cabbage and cauliflower-like aroma and taste profiles. U.S. Pat. No. Re. 30,370 is a reissue of U.S. Pat. No. 3,879,562 (Class 426, subclass 535).
Furthermore, furfuryl thioesters have been suggested in United Kingdom Pat. No. 1,156,480 for possible use in coffee flavors. Ethyl-.alpha.-methyldithiopropionate and ethyl-.alpha.-methyldithiosobutyrate have been said to possess green or onion-like fragrance notes and methanethiol benzoate, methanethiol isovalerate, methanethiol anteisovalerate, methanethiol butyrate, and methanethiol valerate have been said to have milky, rotten egg, cheese or gaseous, cabbage odor-flavor contributions in Netherlands Patent Application No. 68/12,899.
McFadden, et al., Analytical Chemistry 37,560, have suggested the presence of methyl thiohexanoate and thioheptanoate in oil derived from hops, and Buttery, et al., have reported similar work in J. Chromatography 18,399. Shultz, Day and Libbey, "The Chemistry and Physiology of Flavors", Westport, Conn.; Avi. Publishing Co., 1967, especially at page 452, disclose the presence in pineapple flavor of methyl-.beta.-methylthiopropionate and ethyl-.beta.-methylthiopropionate.
Nothing, however, in the prior art, discloses the 4(hydrocarbylthio)acetoacetic esters of our invention having the unexpected, unobvious and advantageous properties for use in augmenting or enhancing the organoleptic properties of foodstuffs and chewing gums.